Tumors inside the eye are rare, and the majority of them are benign — meaning they are not cancerous. The most common lesion is a benign choroidal nevus which is similar to a “mole on the skin.” Choroidal nevi typically do not cause any problems. Occasionally however, the nevus can cause vision loss and rarely it can transform into a melanoma. Therefore, eyes with choroidal nevi should have a dilated eye examination at least once per year.
Other common benign tumors in the eye include choroidal osteoma (bone formation in the eye) and choroidal hemangioma. Although these tumors are not cancerous, they do have the capacity to cause visual loss, and therefore, these tumors should be followed by a retina physician.
Besides choroidal melanoma, other examples of cancerous tumors in the eye include retinoblastoma, which is a rare tumor seen in children, and choroidal metastasis from a primary cancer outside of the eye.